题目内容
引起氟牙症的水源中含氟浓度是
2021-11-10
A.超过2 ppm
B.低于1 ppm，超过0.5 ppm
C.超过1 ppm,小于2.0ppm
D.超过0.2ppm,小于0.5ppm
E.超过0.1 ppm，小于0.5 ppm
试卷相关题目
SQL Error: select id,body,options from ***_enewstiku where sourceid='27640' and id < 2277709 and id<>'2277709' order by id desc limit 5 SQL Error: select id,body,options from ***_enewstiku where sourceid='27640' and id > 2277709 and id<>'2277709' order by id asc limit 5